This is the build I eventually decided on:
"Radiance Genasi" (secret Beyond UltraRare)
- FC: Highest Class / BC: Cleric
- STR -2, CON +2, DEX +2, INT +2, CHA +6, 25% immune fire, free feat: Empower Spell,
free feat: Silent Spell, free feat: Maximize Spell
Base Race: Human
Subrace: Radiance Genasi
Artifact: Lock of Sune Firehair's Hair
Pandect: Shield Profeciency
Tome: Transmutation
Abilities:
STR: 8 (6)
DEX: 14 (16)
CON: 12 (14)
INT: 12 (14)
WIS: 8 (8)
CHA: 18 (24)
Skills:
Concentration
Craft Armor
Discipline
Lore
Tumble
Feats: (8 Pre-epic, 7 Epic, 6 Class Epic, 7 Legendary)
1. Sorcerer - Spell Penetration, Greater Spell Penetration
2. Sorcerer -
3. Sorcerer - Spell Focus (Evocation)
4. Sorcerer - Chr +1 (25)
5. Sorcerer -
6. Sorcerer - Spell Focus (Necromancy)
7. Sorcerer -
8. Sorcerer - Chr +1 (26)
9. Sorcerer - Spell Focus (Illusion)
10. Sorcerer -
11. Sorcerer -
12. Sorcerer - Greater Spell Focus (Necromancy), Chr +1 (27)
13. Sorcerer -
14. Sorcerer -
15. Sorcerer - Greater Spell Focus (Evocation)
16. Sorcerer - Chr +1 (28)
17. Sorcerer -
18. Sorcerer - Greater Spell Focus (Illusion)
19. Sorcerer -
20. Sorcerer - Chr +1 (29)
21. Sorcerer - Epic Spell Penetration
22. Sorcerer -
23. Sorcerer - Epic Spell Focus (Necromancy)
24. Sorcerer - Epic Spell Focus (Illusion), Chr +1 (30)
25. Sorcerer -
26. Sorcerer - Epic Spell Focus (Evocation)
27. Sorcerer - Great Charisma I (31)
28. Sorcerer - Chr +1 (32)
29. Sorcerer - Great Charisma II (33)
30. Sorcerer - Great Charisma III (34)
31. Sorcerer -
32. Sorcerer - Great Charisma IV (35), Chr +1 (36)
33. Sorcerer - Great Charisma V (37)
34. Sorcerer -
35. Sorcerer - Great Charisma VI (38)
36. Sorcerer - Great Charisma VII (39), Chr +1 (40)
37. Sorcerer -
38. Sorcerer - Great Charisma VIII (41)
39. Sorcerer - Great Charisma IX (42)
40. Sorcerer - Chr +1 (43)
------
41. Sorcerer -
42. Sorcerer - Legendary Spell Penetration, Chr +1 (44)
43. Sorcerer -
44. Sorcerer - Chr +1 (45)
45. Sorcerer - LSF (Illusion)
46. Sorcerer - Chr +1 (46)
47. Sorcerer -
48. Sorcerer - LSF (Necromancy), Chr +1 (47)
49. Sorcerer -
50. Sorcerer - Chr +1 (48)
51. Sorcerer - LSF (Evocation)
52. Sorcerer - Chr +1 (49)
53. Sorcerer -
54. Sorcerer - LSF (Transmutation), Chr +1 (50)
55. Sorcerer -
56. Sorcerer - Chr +1 (51)
57. Sorcerer - Great Charisma X (52)
58. Sorcerer - Chr +1 (53)
59. Sorcerer -
60. Sorcerer - Extra Spell 6: Chain Lightning, Chr +1 (54)
-------
61. Sorcerer -
62. Sorcerer -
63. Sorcerer - Paragon Spell Focus (Evocation)
64. Sorcerer -
65. Sorcerer -
66. Sorcerer - Paragon Spell Knowledge (Evocation)
67. Sorcerer -
68. Sorcerer -
69. Sorcerer - Paragon Spell Penetration
70. Sorcerer -
71. Sorcerer -
72. Sorcerer - Paragon Spell Focus: Necromancy
73. Sorcerer -
74. Sorcerer -
75. Sorcerer - Paragon Spell Focus: Transmutation
76. Sorcerer -
77. Sorcerer -
78. Sorcerer - Paragon Spell Focus: Illusion
79. Sorcerer -
80. Sorcerer -
Level 1
--------
Endure Elements
Expeditious Retreat
Protection from alignment
Ray of Enfeeblement
Ice Dagger
Shelgarn's Persistent Blade
Level 2
--------
Ghostly Visage
Flame Weapon
Shock Weapon
Combust
Darkness
Melf's Acid Arrow
Level 3
--------
Keen
Gust of Wind
Clarity
Displacement
Fireball
Level 4
--------
Enervation
Bestow Curse
Remove Curse
Evards Black Tentacles
Elemental Shield
Level 5
--------
Energy Buffer
Lesser Spell Mantle
Lesser Mind Blank
Flensing
Break Enchantment
Level 6
--------
Ethereal Visage
Circle of Death
Disintegrate
Freezing Sphere
Level 7
--------
Great Thunderclap
Delayed Blast Fireball
Banishment
Reverse Gravity
Level 8
--------
Premonition
Horrid Wilting
Sunburst
Bigby's Clenched Fist
Level 9
--------
Weird
Energy Drain
Power Word: Kill
Mordenkainen's Disjunction
Thank you all for the excellent advice.